84. Let X  the time (in 101 weeks) from shipment of a defective product until the customer returns the product. Suppose that the minimum return time is g  3.5 and that the excess X  3.5 over the minimum has a Weibull distribution with parameters a  2 and b  1.5 (see the Indust. Qual. Control article referenced in Example 4.31).

a. What is the cdf of X?

b. What are the expected return time and variance of return time? [Hint: First obtain E(X3.5) and V(X  3.5).]

c. Compute P(X 5).

d. Compute P(5 X

8).